Miniature motor



Aug. 12, 1941. A R my 2,252,600

MINIATURE MOTOR Filed Nov. 24, 1959 s Sheets-Sheet 1 BYfMd ATTORNEY. f

A. LE R. MAY

MINIATURE MOTOR Aug. 12, 1941.

5 Sheets-Sheet 2 Filed Nov. 24, 1959 ATTORNEY.

I Aug. 12, 1941.

LE R. MAY

' MINI-ATUBE MOTOR Filed Neil. 24, 19:59

5 SheefJs-Sheet 5 I outlet 24 of said carburetor.

Patented Aug. 1941 UNITED STATES PATENT. OFFICE MINIATURE MOTOR i Ashton Le Roy May, Detroit, Mich. Application November 24. 1939, Serial No. 305,854 2 Claims. (Cl. 123-195) This invention relates to a miniature motor of the internal combustion type.

It is the object of this invention to provide an eflicient, precision built engine carefully designed for model aeroplanes, race cars, boatsand the like. i

It is the object hereof to provide a light weight engine of greatly simplified structure.

It is the further object to provide an engine having .no pipes, carburetor or clamps bolted to tions by way of example and are not intended to limit the scope of this invention.

Referring to the drawings: Figure 1 is aside elevation of the motor. Figure 2 is an end elevationthereoi.

Figure 3 is a section on line 3-3 of Figure 2.

Figure 4 is an enlarged fragmentary section of a portion of the motor, and

Figure 5 is an enlarged section of the carburetor.

As illustrated in Figure 3, the crankshaft Ii with nut l2 and washer l3 joumaled' through the oilite or other type of bearing II, has sen cured thereon the timer cam II and washer it integral therewith.

The two washers II and II are designed to o eratively secure a propeller blade ii therebetween.

The crank case housing I! designed to also support the bearing i4, is closed by a back cover plate I! suitably bolted thereto (bolts not shown) said cover plate being centrally bored to rotatably journal the rotary valve 20. The gasoline tank 2i with carburetor 22 transversely disposed andsecured therein is threadabiy attached to the hollow extended portion 23 ot the back cover plate It by means or theinteriorly threaded Thus secured the end portion or the gas tank registers with the peripheral edge or. the back cover plate I! to complete the closure.

The cylinder 25 suitably bolted to the top or crank case II with spark plug 28 and projecting cooling flns 21 has longitudinally disposed there- .in the cast steel sleeve ish.

The piston 29 with bailie plate 30, designed to reciprocate within sleeve 24 is actuated by piston 24 honed to a mirror finrod 3i secured thereto by bearing 32 and pin 33.

operatively secured to the crank shalt II to rotate therewith is the crank-throw 34 designed to. counterbalance piston-rod ii, the latter being eccentrically mounted to said crankthrow by. means of a bearing and crank pin 33', threaded thereto.

, Referring to Figure 4, it will be seen that the rotary valve 20 connected with the carburetor outlet 24 is rotatably journaled transversely within the back cover plate it.

Crank pin 33' has a projection 35 upon its end to' which is operatively and pivotally secured a crank 36, the opposite end or which is fixedly mounted on the base portion of the rotary valve at'point 31. Consequently the rotary valve is revolved with the crank shaft and a mixture of gasoline and air supplied to the compression chamber 38 to be acted upon by each compression movement or the piston.

The circular opening a in the side or the valve communicates once each revolution with channel 40 formed within the back cover plate is leading into the crank case. A by-pass 4i formed upon the outside wall of cylinder 2! communicates with the interior of said crank case on one end thereof and with the cylinder chamber 38 on the other hand. However. it will be noted that access to the combustion chamber is cut oi! by piston 29 as the same rises into compression. After an explosion, the resulting downward motion or the piston,- opens the exhaust ports 42 on one side of the baiile plate 30, while simultaneously a new mixture is allowed to enter the'cylinder chamber through by-pass 4|, entering said chamber on the opposite site oi baiiie 3|. 7

Referring now to Figures 4 and 5, it will beseen that the carburetor 22 is entirely within the gasoline tank 2|. The carburetor tube 43 with air intake has a. gasoline inlet tube 45 communicating with the tank interior. The flow o! gasoline into the carburetor through opening 46 in tube 42. is regulated by the needle 41 Journaled through the needle guide 42, the latter being centrally disposed within the carburetor tube 43;

The interiorly threaded collar 49, through which the needle 41 is operatively and resiliently journaled by means of the tension spring I provides means for manual adjustment of the gas inlet opening 4 to-regulate the volatile mixture of air and gasoline entering the carburetor outlet The web portion ll integral-with the gasoline tank and having a central opening for receiving the carburetor outlet 24, provides a suitable closure for the tank.

Referring to Figures 2 and 3 it will be seen that the timer arm 52 is provided with a split sleeve 53 upon its lower extremity whereby said am may be loosely clamped upon the bearing II for manual regulation thereof.

The forward end 54 of said timer arm is provided with a contact point 55 to intermittently register with contact point 56 which is centrally disposed upon the leaf spring 51. Said leaf spring mounted upon the forward portion 54 of the timer arm by means of a screw 58 in insulated relation with respect to the contact point by it registers with the aforementioned timing cam IS, the latter being fixedly mounted upon the crank shaft. By this. means electric contact is made and broken intermittently by the contact carrying leaf spring 51 for completing a circuit between a battery, coil and spark plug for producing an intermittent spark in the aforesaid combustion chamber 38. The obvious simpliclty of the timing mechanism, and the ease with which it may be adjusted tend to produce an engine of high efficiency. The emciency is further enhanced by the rotary valve 20 for conducting a volatile vapor directly through the crank case to the compression chamber.

The rotary valve eliminates all back pressure in the carburetor by intermittently closing off of the motor is greatly enhanced and at the same 7 time insures a greater efficiency when used with model aeroplanes.

Having described my invention, reference should now be had to the claims which follow for 55, downwardly depends from said screw wheredetermining the scope thereof.

1 claim:

1. An internal combustion engine comprised of a crankcase, a crankshaft, a crankcase cover plate, a fuel tank, a carburetor within said fuel tank centrally secured to said cover plate for retaining said tank, said cover plate having an opening communicating with the crankcase and with the carburetor, a hollow cylindrical crankshaft actuated valve journaled therein, having a lateral opening, there being a radial passage in said cover plate communicating with said lateral opening and with the crankcase.

2. An internal combustion engine comprised ,of a cylindrical crankcase with an elongated journaled therein, having a lateral opening,

there being a radial passage in said cover plate communicating with said lateral opening and with the crankcase.

. ASHTON LE ROY MAY. 

